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Let's face it. We hardly ever have the luxury of focusing on one thing anymore. No matter where we are, our gadgets are there, too, ready to beep, ping, display an alert, or serenade us with our chosen ring-tone. So we live with it all. But do we realize how much we're losing this way?
There is mounting evidence that the cost of constant interruptions is huge. A study by Bowman and her associates (1) demonstrated this experimentally. Psychology students who were asked to read a five-page article online were told that they would read it under one of three conditions: (a) receiving and responding to instant messages (IMs) intermittently while reading; (b) not receiving IMs; or (c) responding to IMs before reading. The researchers measured the time it took students to read the article as well as their memory for its content.
The big take-away from the research is that students who were interrupted by the instant messages took much longer. Students who IMd while reading took 46 minutes to read the article, not including the almost 3 minutes they used to read and answer the IMs. The students who didn't receive instant messages took about 37 minutes. Interestingly, the students who answered IMs before reading the article finished in only about 29 minutes.
In other words, being interrupted to read and reply to IMs added either 22% or 59% to the time it took to read the article, depending on which other condition you choose as a base-line. Although the authors did not anticipate that responding to IMs before reading the article would improve reading speed, they reasoned that the students who got the IMs before they started reading probably figured out that they were not going to be interrupted while reading. (I'll call this the "focused" group.) In other words, the students who didn't receive IMs before reading might have been anticipating the interruptions (whether they ultimately came or not), and this anticipation might have been distracting in itself, slowing down the process of reading.
Surprisingly, the three groups did not differ in their performance on the memory test. Apparently, the extra time was put to use in rereading passages and trying to remember what had been learned before. Also, it is not clear what type of questions were posed about the article. A study by Foerde and her co-workers (2) also demonstrated no difference in learning between dual-task and single-task trials when the test measured habit learning (asking for the knowledge in the same form it was initially presented in). However, when the questions required generalization or explicit knowledge of the principles underlying the correct response, single-task learners performed much better.
But even if you'd be happy to score well on a test of rote memory, are you willing to spend that much more time studying or reading something to get the same result? Why not read and respond to your IM's before starting, turn off your alerts while reading, and THEN check your messages or do something relaxing in all that valuable time you've saved.
(1) Bowman, L. L., Levine, L. E., Waite, B. M., & Gendron, M. (2010). Can students really multitask? An experimental study of instant messaging while reading. Computers & Education, 54, 927-931.
Foerde, K., Knowlton, B., & Poldrack, R. A. (2006). Modulation of competing memory systems by distraction. Proceedings of the National Academy of Sciences, 103, 11778-11783. www.pnas.org/cgi/doi/10.1073/pnas.0602659103
